The present invention relates to a RAID (redundant array of inexpensive disk) device, especially to a RAID system with command processing and data transmission adapting ability, whereby the buffer memory is saved and the data of new disk driver can be restored.
The prior art RAID system, as shown in FIG. 1, comprises at least a host computer 10, a host bus 12, a RAID controller 14 connected to the host computer 10 through the host bus 12, a plurality of hard disks 160 and 162 connected to the RAID controller 14. The RAID controller 14 comprises at least one functional controller 142 connected to the host bus 12 and a data buffer memory 144 connected to the functional controller 142. The host computer 10 issues request command to hard disks 160 and 162 through the RAID controller 14 for read/write operation. After the hard disks 160 and 162 are ready, the hard disks 160 and 162 send ready command to the host computer 10 through the RAID controller 14. The data to be read or written are temporarily stored in the data buffer memory 144 to reduce transfer delay time and then dispatched to the host computer or the hard disks 160 and 162 according to the regulation of functional controller 142.
The above described RAID system has the advantages of large storage capacity, fault tolerance, fast accessing speed, and automatic data rebuild and backup. However, the functional controller is involved in both read and write operation, the accessing speed is delayed. Moreover, considerable buffer memories are required, the cost of the conventional RAID system is high.
It is an object of the present invention to provide a RAID system with command processing and data transmission adapting ability, wherein a controller is incorporated to process command and regulate channel for data transmission such that the buffer memory is saved and cost is reduced.
It is another object of the present invention to provide a RAID system with command processing and data transmission adapting ability, wherein a data hub and a data processing unit are incorporated to automatically rebuild data with shorted time.
It is still another object of the present invention to provide a RAID system with command processing and data transmission adapting ability, wherein a data processing unit is incorporated to select data storage mode and facilitate the RAID0 and RAID1 architecture.
It is still another object of the present invention to provide a RAID system with command processing and data transmission adapting ability, wherein an OR gate is incorporated to a data processing unit to reduce the risk of transmission error and computer failure.
It is still another object of the present invention to provide a RAID system with command processing and data transmission adapting ability, wherein each hard disk driver is connected to a master hard disk and a slave hard disk such that two corresponding master hard disks form a master mirror RAID system and two corresponding slave hard disks form a slave mirror RAID system.
The various objects and advantages of the present invention will be more readily understood from the following detailed description when read in conjunction with the appended drawing, in which: